Dressing apparatus for grinding wheels



Feb. 21, 1961 E. R. DUNN DRESSING APPARATUS FOR GRINDING WHEELS 3 Sheets-Sheet 1 Filed March 19, 1959 Feb. 21, 1961 E. R. DUNN DRESSING APPARATUS FOR GRINDING WHEELS 3 Sheets-Sheet 2 INVENTOR ELMA/V R,Dl//V/V ATTORNEY Filed March 19, 1959 Feb. 21, 1961 E. R. DUNN 2,972,343

DRESSING APPARATUS FOR GRINDING WHEELS Filed March 19, 1959 a Sheets-Sheet s INVENTOR ELMA/V 1? .DU/V/V TTO R N EY Unite Elman R. Dunn, Be loit, Wis, assignor t o Gardner Machine Company, Beloit, Wis.

Fiia'Mar. 19, 19s9, ser.' i m-800,478

Claims. Cl. 125-11 This" invention relates to a dressing-device for a disct'y'pe grinder.

Previous dressers used on this type of machine have been lacking in rigidity and usually have required great maintenance care. If the operation of a machine requires a change in type of dresser, it is necessary to change the entire dresser bar.

It is, therefore, an object of this invention to provide a dressing device for disc grinders in which the dresser bar will be supported with maximum rigidity over a reasonably long period of usage with little maintenance attention.

Another object is to provide means whereby a variety of dressing tools may be attached to a dresser bar.

Figure 1 is a partial end elevation of the abrasive disc and hood showing the method of mounting the dressing device.

Figure 2 is a rear elevation, partly in section, on line 2--2 of Figure 1, showing the means for transmitting movement to the dresser bar and for preventing rotation of said dresser bar.

Figure 3 is a sectional elevation on line 3-3 of Figure 1, showing certain elements of the driving means for the dresser traverse mechanism.

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Figure 4 is a partial sectional plan view on line 4-4 shown in Figure 5.

The upper portion 13 of hood 10 is formed to support housing 14. Housing 14 has a vertical bore 21 in which *dresser bar 20 is slidably supported.- The supports for dresser bar 26 consists of two ball sleeves 25 and 26.

.Each of said ball sleeves 25 and 26 is split longitudinally :at 27 and 28 respectively.

Suitable sealing means 30 and 31 is provided at the upper and lower ends of bore 21 to retain lubricant in ball sleeves 25 and 26 and to prevent foreign matter from entering said ball sleeves.

Housing 14 is split longitudinally at 15. Clamping screws 16 are provided to clamp housing 14 about ball sleeves 25 and 26 in order to preload said ball sleeves and thus provide a rigid mounting for dresser bar 20. Split 15 in housing 14 is filled with a suitable plastic material which adheres to the side of the split portion and seals housing 14 against coolant or grit in all positions of adjustment.

The means for effecting vertical movement of dresser bar 20 consists of a bracket 49 having a vertical longitudinal recessed portion 41, on each side of which is secured guide strips 42 and 43.

Guide member 50 is suitably attached to the upper end of dresser bar 20. Member 50 has a portion 51 extending into the recessed portion 41 in bracket 40.

2', Portion 51 has a air of peripherallyfopposed uide-rulers 55 and 56 rotatably mounted therein. Rollers 55 and 56 are supported on shafts 57 and 58respectively; Shafts" 57 and 58 are rotatably mounted in eccentric bushings 59 and 60. Suitable means (not shown) may be'pro vided to rotate bushings 5 9 and 60 toadjust-rollers' 55 and' 56 into fi-rm contact with guidestrips 4'2 and 43.

The. means for eiiecting vertical movement of dresser bar 20 consists of a ball bearing screw and acconipanying nut which is threaded into portion 51 of guide member 50. The lower end of screw 65 is suitably attachedto vertical shaft rotatably mounted in the} upper portion of housing 14. Shaft 70has aworm" wheel 71 keyed thereto and engaginga worm gear 72 on shaft 73 alsorotatably mounted in housing 14. Shait 73 extends from housing 14 to receive sprocket 74 con: nected by chain 75 to sprocket 76 on motor 77. Motor 77 is supported on base portion 78 on housing 14.

Figure 5 discloses a type of dresser known as a thrufeed dressing tool shown here for the purpose of illustration. It consists of a bracket located on dresser bar 20 by means of a pilot pin 91 and secured to said dresser bar by means of screws 92. A pair of diamond holders 95 and 96 are adjustably mounted on bracket 90. Diamond tools 97 and 98 are suitably mounted on diamond holders 95 and 96 so as to engage the operative surfaces of discs 11 and 12.

Pilot pin 91 and screws 92 may be used to attach other types of dressing tools to dresser bar 20. Such dressing tools are designed to be attached in this manner.

The operation of this invention is believed to be obvious in view of the above description of the drawings.

I claim:

1. A dressing device for dressing the opposed discs of a double disc grinder comprising a cylindrical dresser bar, an adjustable tool holder attached to said dresser bar, opposed dressing tools in said holder, a housing for supporting said dresser bar for axial movement therein, means for rigidly supporting said dresser bar in said housing comprising an adjustable ball bushing, a slot in said housing, means for clamping said housing about said bushing, a resilient plastic material for sealing said slot in said housing in all positions of adjustment to prevent foreign matter from reaching said ball bushing, ring-like sealing members at each end of said housing which permit a slight film of lubricant to move out of said housing with the movement of said dresser bar but which wipes the dresser ba-r clean as it moves into said housing, a guide bracket on said housing parallel with said dresser bar, a guide member slidably mounted onsaid guide bracket and means for etfecting movement of said guide member on said guide bracket, said guide member being attached to said dresser bar.

2. A dressing device for dressing the opposed discs of a double disc grinder comprising a cylindrical dresser bar, an adjustable holder removably attached to said dresser bar, opposed dressing tools in said tool holder for engaging said opposed discs, a housing for supporting said dresser bar for axial movement therein, means for rigidly supporting said dresser bar in said housing comprising longitudinally spaced adjustable ball bushings, a slot in said housing and means for clamping said housing about said bushings.

3. A dressing device for dressing the opposed discs of a double disc grinder comprising a cylindrical dresser bar, an adjustable dressing tool holder removably attached to said dresser bar, opposed drmsing tools in said tool holder for engaging said opposed discs, a housing for supporting said dresser bar for axial movement there- 0 in, means for rigidly supporting saiddresser bar in said Patented Feb. 21, 1961 said housing about said bushings, means for efiecting axial movement of said dresser bar comprising a guide bracket on said housing, a guide member slidably mounted on said guide bracket, means for effecting movement of said guide member on said guide bracket, said guide member being attached to said dresser bar.

4. A dressing device for dressing the opposed discs of a double disc grinder comprising a cylindrical dresser bar, an adjustable dressing tool holder attached to said dresser bar, opposed dressing tools in said tool holder for engaging said opposed discs, a housing for supporting said dresser bar for axial movement therein, means for rigidly supporting said dresser bar in said housing, a guide bracket on said housing separate from said dresser bar, a guide member slidably mounted on said guide bracket, an arm connecting said guide member to said dresser bar and means connected to said guide member for effecting axial movement of said guide member and said dresser bar.

5. A dressing device for dressing the opposed discs of a double disc grinder comprising a cylindrical dresser bar, an adjustable dressing tool holder removably attached to said dresser bar, opposed dressing tools in said dressing tool holder for engaging said opposed discs, a housing for supporting said dresser bar for axial movement there in, means for rigidly supporting said dresser bar in said housing comprising an adjustable ball bushing, a slotin- References Cited in the file of this patent UNITED STATES PATENTS Summers June 30, 1936 Black Jan. 22, 1952 

